U.S. patent number 6,457,132 [Application Number 09/343,626] was granted by the patent office on 2002-09-24 for calendar-based power management.
This patent grant is currently assigned to International Business Machines Corporation. Invention is credited to Kenneth Wayne Borgendale, Herman Rodriguez.
United States Patent |
6,457,132 |
Borgendale , et al. |
September 24, 2002 |
Calendar-based power management
Abstract
Upon creation of an event or activity entry within a calendar,
the user is prompted to specify a power management mode to
associate with the entry if the entry is not of a predefined type.
Predefined entry types may be associated with default power
management modes which the user may modify. When an event or
activity entry associated with a non-null power management mode is
reached, the calendar sends a power management event notification
to the power manager, which responds appropriately. Thus, a user
may specify that the system, if powered on, should automatically
shut down for the duration of a planned vacation identified by an
entry within the calendar. The system may thus distinguish between
events during which the user is unavailable (e.g., on a business
trip or at a remote meeting) from events during which the user is
available but perhaps not actively using the system for a period.
The calendar event power management modes complement and refine the
preconfigured system power management schemes to take into account
the user's schedule of activities.
Inventors: |
Borgendale; Kenneth Wayne
(Austin, TX), Rodriguez; Herman (Austin, TX) |
Assignee: |
International Business Machines
Corporation (Armonk, NY)
|
Family
ID: |
23346890 |
Appl.
No.: |
09/343,626 |
Filed: |
June 30, 1999 |
Current U.S.
Class: |
713/320 |
Current CPC
Class: |
H04W
52/0258 (20130101); G06F 1/3203 (20130101); G06F
1/3246 (20130101); H04M 1/72451 (20210101); Y02D
30/70 (20200801) |
Current International
Class: |
G06F
1/32 (20060101); H04M 1/73 (20060101); H04M
1/725 (20060101); H04M 1/72 (20060101); G06F
001/32 () |
Field of
Search: |
;713/300,310,320 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Auve; Glenn A.
Attorney, Agent or Firm: LaBaw; Jeffrey S. Mims, Jr.; David
A. Bracewell & Patterson, L.L.P.
Parent Case Text
RELATED APPLICATIONS
The present invention is related to the subject matter of the
following commonly assigned, copending U.S. patent applications
Ser. No. 09/343,628 entitled "CALENDAR-INDUCED PROGRAM EXECUTION"
and filed Jun. 30, 1999; and Ser. No. 09/343,629 entitled
"CALENDAR-INDUCED DESKTOP SECURITY" and filed Jun. 30, 1999. The
content of the above-referenced applications is incorporated herein
by reference.
Claims
What is claimed is:
1. A method of calendar based power management, comprising:
creating a calendar entry that does not indicate an associated
power management parameter within a user calendar; associating a
calendar event type with the calendar entry; determining an
associated power management parameter as a function of the
associated calendar event type, wherein the associated power
management parameter specifies a power management mode to be
initiated upon reaching a start time for the calendar entry.
2. The method of claim 1, wherein the step of creating a calendar
entry within a user calendar further comprises: setting the
associated power management parameter to a predefined value for the
associated calendar event type of the calendar entry.
3. The method of claim 1, wherein the step of creating a calendar
entry within a user calendar further comprises: prompting the user
to specify the associated power management parameter.
4. The method of claim 1, wherein the step of determining the
associated power management parameter with the calendar entry
further comprises: associating an identifier of a power management
mode with the calendar entry.
5. The method of claim 1, wherein the step of determining the
associated power management parameter with the calendar entry
further comprises: associating a power management event with the
calendar entry.
6. A method of calendar based power management, comprising:
determining whether a start time for a calendar entry that does not
indicate an associated power management parameter within a user
calendar has been reached, wherein the calendar entry has an
associated calendar event type; responsive to determining that the
start time has been reached, determining whether a power management
parameter is associated with the associated calendar event type;
and responsive to identifying a power management parameter
associated with the associated calendar event type, performing a
power management process utilizing the power management
parameter.
7. The method of claim 6, wherein the step of determining whether a
power management parameter is associated with the associated
calendar event type further comprises: determining whether a power
management mode has been specified for the calendar entry.
8. The method of claim 6, wherein the step of performing a power
management process utilizing the power management parameter further
comprises: sending a power management event notification
corresponding to the power management parameter to a power manager;
and entering a power management mode specified by the power
management event notification.
9. The method of claim 6, wherein the step of performing a power
management process utilizing the power management parameter further
comprises: responsive to detecting system activity conflicting with
a power management mode specified by the power management
parameter, delaying or cancelling initiation of the power
management mode.
10. The method of claim 6, wherein the step of performing a power
management process utilizing the power management parameter further
comprises: setting a power management event to occur at a
subsequent time; and entering a power management mode specified in
the power management parameter.
11. A system for calendar based power management, comprising: a
user calendar containing a calendar entry that does not indicate an
associated power management parameter; and a power management
parameter associated with the calendar entry as a function of a
calendar event type for the calendar entry, wherein the associated
power management parameter specifies a power management mode to be
initiated upon reaching a start time for the calendar entry.
12. The system of claim 11, wherein the calendar entry further
comprises: a predefined value for the calendar event type of the
calendar entry which is employed in setting the associated power
management parameter.
13. The system of claim 11, wherein the power management parameter
further comprises: a use-specified power management mode.
14. The system of claim 11, wherein the power management parameter
further comprises: a power management event.
15. A system for calendar based power management, comprising: a
user calendar containing a calendar entry that does not indicate an
associated power management parameter, wherein the calendar entry
has an associated calendar event type; and a power manager
performing power management processes in response to receiving
power management event notifications from the user calendar,
wherein the user calendar determines whether a start time for a
calendar entry within the user calendar has been reached, and
responsive to determining that the start time has been reached,
determines whether a power management parameter is associated with
the calendar entry as a function of the associated calendar event
type, and responsive to determining a power management parameter is
associated with the calendar entry, sends a power management event
notification to the power manager.
16. The system of claim 15, wherein the user calendar determines
whether a power management mode has been specified for the calendar
entry, and, responsive to finding a power management mode specified
for the calendar entry, sends a power management event notification
corresponding to the power management mode to the power
manager.
17. The system of claim 16, wherein the power manager initiates a
power management mode specified by the power management event
notification.
18. The system of claim 17, wherein the power manager sets a power
management event to occur at a subsequent time before initiating
the power management mode specified in the power management
parameter.
19. The system of claim 15, wherein the user calendar checks for
system activity conflicting with a power management mode specified
by the power management parameter, and, responsive to detecting
system activity conflicting with the power management mode, delays
or cancels sending the power management event notification.
20. The system of claim 15, wherein the power manager checks for
system activity conflicting with a power management mode specified
by the power management parameter, and, responsive to detecting
system activity conflicting with the power management mode, delays
or cancels initiating the power management event mode.
21. A computer program product within a computer usable medium,
comprising: instructions for creating a calendar entry that does
not indicate an associated power management parameter within a user
calendar; instructions for associating a calendar event type with
the calendar entry; instructions for determining an associated
power management parameter as a function of the associated calendar
event type, wherein the associated power management parameter
specifies a power management mode to be initiated upon reaching a
start time for the calendar entry.
22. The computer program product of claim 21, wherein the
instructions for creating a calendar entry within a user calendar
further comprise: instruction for setting the associated power
management parameter to a predefined value for the associated
calendar event type of the calendar entry.
23. The computer program product of claim 21, wherein the
instructions for creating a calendar entry within a user calendar
further comprise: instructions for prompting the user to specify
the associated power management parameter.
24. The computer program product of claim 21, wherein the
instructions for associating a power management parameter with the
calendar entry further comprise: instructions for associating an
identifier of a power management mode with the calendar entry.
25. The computer program product of claim 21, wherein the
instructions for associating a power management parameter with the
calendar entry further comprise: instructions for associating a
power management event with the calendar entry.
26. A computer program product within a computer usable medium,
comprising: instructions for determining whether a start time for a
calendar entry that does not indicate an associated power
management parameter within a user calendar has been reached,
wherein the calendar entry has an associated calendar event type;
instructions, responsive to determining that the start time has
been reached, for determining whether a power management parameter
is associated with the associated calendar event type; and
instructions, responsive to identifying a power management
parameter associated with the associated calendar event type, for
performing a power management process utilizing the power
management parameter.
27. The computer program product of claim 26, wherein the
instructions for determining whether a power management parameter
is associated with the calendar entry further comprise:
instructions for determining whether a power management mode has
been specified for the calendar entry.
28. The computer program product of claim 26, wherein the
instructions for performing a power management process utilizing
the power management parameter further comprise: instructions for
sending a power management event notification corresponding to the
power management parameter to a power manager; and instructions for
entering a power management mode specified by the power management
event notification.
29. The computer program product of claim 26, wherein the
instructions for performing a power management process utilizing
the power management parameter further comprise: instructions,
responsive to detecting system activity conflicting with a power
management mode specified by the power management parameter, for
delaying or cancelling initiation of the power management mode.
30. The computer program product of claim 26, wherein the
instructions for performing a power management process utilizing
the power management parameter further comprise. instructions for
setting a power management event to occur at a subsequent time; and
instructions for entering a power management mode specified in the
power management parameter.
Description
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention generally relates to power management in data
processing systems and other electrically powered devices and in
particular to power management keyed to a user activities. Still
more particularly, the present invention relates to calendar-based
power management allowing automatic power management to conform to
a user's scheduled activities.
2. Description of the Related Art
Current power management schemes employed in mobile or desktop data
processing systems, personal digital assistants (PDAs) or handheld
organizers, "smart" phones, or the like are typically keyed to one
of the following: inactivity based, usually with respect to the
keyboard, the mouse, network, or disk activity; power mode based,
usually with respect to whether battery or AC power is employed;
and "location" based, usually with respect to whether the device is
docked or undocked.
The principle problem with such power management criteria is the
failure to accommodate a user's schedule of activities. For
example, if a system is configured to employ a power management
scheme based only on power source (AC versus battery) while the
machine is running on battery, and the user goes to a long meeting,
upon returning he may find a discharged battery. Employing an
activity-based power management scheme in conjunction with the
power-mode based scheme to cause the system to enter "sleep" mode
after a specified period of inactivity may prevent battery
discharge under the circumstances described above. However, this
may also cause the system to enter "sleep" mode at other times when
the user is working but merely does not utilized the system for the
timeout period (e.g., while reading or reviewing paperwork).
As another example, if a machine is left running on AC power while
a user goes on vacation, the machine may stay running--and
consuming power--throughout the time the user is on vacation.
Again, the addition of an activity-based timeout period might
address the particular instance of the user being on vacation, but
could carry over to other times when it would be undesirable for
the system to power down merely because of a period of inactivity.
The system is unable to distinguish between events or periods when
the user might desire automatic shutdown from those in which
automatic shutdown would be a nuisance.
It would be desirable, therefore, to enable power management
systems to take into account a user's schedule of activities in
determining whether to enter a power management cycle.
SUMMARY OF THE INVENTION
It is therefore one object of the present invention to provide
improved power management in data processing systems and other
electrically powered devices.
It is another object of the present invention to provide power
management keyed to a user's activities in data processing systems
and other electrically powered devices.
It is yet another object of the present invention to provide
calendar-based power management allowing automatic power management
to conform to a user's scheduled activities.
The foregoing objects are achieved as is now described. Upon
creation of an event or activity entry within a calendar, the user
is prompted to specify a power management mode to associate with
the entry if the entry is not of a predefined type. Predefined
entry types may be associated with default power management modes
which the user may modify. When an event or activity entry
associated with a non-null power management mode is reached, the
calendar sends a power management event notification to the power
manager, which responds appropriately. Thus, a user may specify
that the system, if powered on, should automatically shut down for
the duration of a planned vacation identified by an entry within
the calendar. The system may thus distinguish between events during
which the user is unavailable (e.g., on a business trip or at a
remote meeting) from events during which the user is available but
perhaps not actively using the system for a period. The calendar
event power management modes complement and refine the
preconfigured system power management schemes to take into account
the user's schedule of activities.
The above as well as additional objectives, features, and
advantages of the present invention will become apparent in the
following detailed written description.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set
forth in the appended claims. The invention itself however, as well
as a preferred mode of use, further objects and advantages thereof,
will best be understood by reference to the following detailed
description of an illustrative embodiment when read in conjunction
with the accompanying drawings, wherein:
FIG. 1 depicts a block diagram of a data processing system in which
a preferred embodiment of the present invention may be
implemented;
FIG. 2 is a diagram of a calendar based power management system in
accordance with a preferred embodiment of the present invention;
and
FIGS. 3A-3B depict high level flow charts for processes of
establishing and employing calendar-based power management in
accordance with a preferred embodiment of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the figures, and in particular with reference
to FIG. 1, a block diagram of a data processing system in which a
preferred embodiment of the present invention may be implemented is
depicted. Data processing system 100 includes a processor 102,
which is connected in the exemplary embodiment to a level two (L2)
cache 104, connected in turn to a system bus 106.
Also connected to system bus 106 is system memory 108 and
input/output (I/O) bus bridge 110. I/O bus bridge 110 couples I/O
bus 112 to system bus 106, relaying and/or transforming data
transactions from one bus to the other. Peripheral devices such as
nonvolatile storage 114, which may be a hard disk drive, compact
disk read-only memory (CD-ROM) drive, or digital video disk (DVD)
drive, and keyboard/pointing device 116, which may include a
conventional mouse, a trackball, or the like, are connected to I/O
bus 112. Data processing system 100 further includes graphics
adapter 116 connected to system bus 106, receiving primitives for
rendering from processor 102 and generating pixels for display
120.
The operation of data processing system 100 is well known to those
skilled in the art. A basic input/output system (BIOS), power-on
self-test (POST), and various startup routines initialize the
hardware and permit interaction between hardware components. An
operating system, such as a version of the Windows operating system
available from Microsoft Corporation of Redmond, Wash., provides a
platform for execution of applications and for basic user
interaction, such as display of information or manipulation of a
cursor within the display by a pointing device. Operating system
device drivers allow software components to interact with and
control hardware components. Data processing system may be
connected to a server 122 via a communications link 124 in
accordance with known networking techniques. In the present
invention, either the operating system includes a calendar utility
or a calendar application runs on top of the operating system.
Additionally, the operating system includes a power manager, and
may include particular hardware employed for power management
(e.g., a controller).
Referring to FIG. 2, a diagram of a calendar based power management
system in accordance with a preferred embodiment of the present
invention is illustrated. Calendar-based power management system
202 includes a power manager 204 and a calendar 206.
Power manager 204 tracks the state of various system parameters
208, such as whether the current power source is AC or a battery,
the time since the last keyboard or mouse activity, and whether the
system is docked. Based on the values of these parameters 208 at
any given time, power manager 204 maintains the system in one of
several power management modes, such as fully powered, "sleep" or
reduced power mode, and powered down. Power manager 204 may also
cause the system to change between power management modes when the
value of one or more parameters 208 changes.
Calendar 206 contains a plurality of data objects or records 210
for each date within a range of dates, such as all dates within a
given year and/or each date for which some event is created. The
user may create entries 212a-212n within any given date 210n, which
entries 212a-212n specify events or activities within the user's
schedule. Such events or activities may include "Vacation," "Trip,"
"Meeting," "Out-of-Office Meeting," etc. The events or activities
specified by an event entry 212a-212n may be one of a number of
predefined events or activities, or may be a user-defined event or
activity.
During creation of an event entry 212a-212n, the user is prompted
(as a menu option, for example) to specify a power management mode
214a-214n in which the system should be placed for the duration of
the event. Thus, for example, for a vacation entry, a user may
specify that the system should be powered down, since leaving the
machine on would be energy wasteful. If the user has not turned the
system off prior to going on vacation, the power manager will shut
down the system for the user. Particular dates 210n, such as
holidays, may also have an associated power management mode
218.
The power management mode 214a-214n may be predefined for certain
event or activity types, such as "Vacation" or "Meeting." Such
predefined power management modes 214a-214n may simply be a default
for that event type, and the user may be provided the option of
overriding or altering the predefined power management mode
214a-214n. If the power management mode 214a-214n is not predefined
for a particular event type, or if an event entry 212a-212n is
created which is not a predefined event type, the user is prompted
to set the power management mode 214a-214n in which the system
should be placed for the duration of the event.
To enable the user to set the power management mode 214a-214n for
an event entry 212a-212n, a list of possible power management modes
may be displayed to the user. Alternatively, the user may be
prompted to answer a series of questions (e.g., "Will you be
needing the system for this event?"), and the power management mode
214a-214n set for the event entry 212a-212n based on the user's
answers (i.e. a "wizard").
During subsequent system operation, when the date and time for an
event entry 212a-212n is reached, calendar 206 automatically sends
the appropriate power management event to the operating system
power manager 204. Power manager 204 may then determine whether the
specified power management mode should be entered. It is preferable
that calendar 206 not blindly send the power management event
notification to the power manager 204, and that the power manager
204 not automatically enter the specified power management mode for
the duration of the event, since other circumstances may override
the calendar event entry 212a-212n.
For example, if a user should skip a scheduled meeting for which an
event entry was created in order to continue working, calendar 206,
upon detecting ongoing activity for some period following the
scheduled beginning of the event, may skip sending the power
management event notification to the power manager 204. Similarly,
power manager 204 may detect the continued presence of the user via
system activity, and simply ignore the power management event sent
by calendar 206. In either case, the result is that the system
remains in a prior, existing power management mode until at least
the next event entry within calendar 206.
Whenever the date and time for the beginning of a scheduled user
activity within calendar 206 is reached while a system is running,
calendar 206 updates power manager 204 with the appropriate power
management mode. For long events, such as a week-long business trip
or vacation, calendar 206 may update power manager 204 with the
appropriate power management mode 214a-214n on a periodic basis
(e.g., daily). Thus, if the user gets a late start on the event and
the power management mode is initially ignored due to detection of
ongoing system activity, the applicable power management mode will
eventually be entered for the duration of the event.
The user's calendar 206 and the power management mode 214a-214n
associated with event entries 212a-212n within calendar 206
complement and refine pre-configured power management schemes. For
example, the user may specify that the system should be powered
down following detection of a predetermined period of inactivity
during an event entry 212a-212n. This allows inactivity-based power
management to be employed for periods when the user is scheduled
not to be available, but not during periods when the user is
scheduled to be working with the system. Accordingly, the benefit
of inactivity-based power management may be obtained without the
nuisance of a system shut down while a user is working.
While a data processing system is employed as the exemplary
embodiment, the present invention finds application in any device
employing power management and providing a user calendar function.
This includes personal digital assistants such as the popular
"Palm" line of handheld organizers, and smart phones. Specific
refinements appropriate to different types of devices are also
possible. For instance, if the present invention is implemented
within a smart phone, in which a user schedules travel (in the
calendar function) to a city where the no wireless carrier provides
service to the user, the smart phone may automatically shut down
and remain powered down for the duration of the trip.
With reference now to FIGS. 3A and 3B, high level flow charts for
processes of establishing and employing calendar-based power
management in accordance with a preferred embodiment of the present
invention are depicted. The process of establishing calendar based
power management, depicted in FIG. 3A, begins with step 302, which
depicts an event or activity entry being created within a user's
calendar.
The process then passes to step 304, which depicts a determination
of whether a new user-defined event entry type (i.e., not
predefined or previously user-defined) was created. If not, the
process proceeds to step 306, which illustrates a determination of
whether a power management mode is specified for the event entry
type created. Predefined event entry types (e.g., "Vacation") may
have associated default power management modes (typically "off" for
the example of "Vacation") within their definition. Alternatively,
the user may have previously defined the event entry type selected
(e.g., "Mom's house") for the event or activity entry created, and
specified a power management mode to be associated with event
entries of that type.
If a new user-defined event type is created (step 304), or if no
power management mode is specified for the entry type of the entry
just created (step 306), the process proceeds instead to step 308,
which illustrates displaying a list of possible power management
modes for a user, and then to step 310, which depicts prompting the
user to specify a power management mode for the event entry just
created. The process then passes to step 312, which illustrates a
determination of whether a power management mode has been specified
for the event entry just created within the user's calendar.
If a power management mode is defined for an event type of the
newly-created event entry (step 306), or if the user specifies a
power management mode to associate with the event entry (step 312),
the process proceeds to step 314, which depicts setting the power
management mode as specified or defined for the just-created event
entry. Otherwise, the process proceeds instead to step 316, which
illustrates setting the power management mode associated with the
event entry to a null value. The null value is only for the
calendar program, and the power management module will not utilize
this null value but will instead merely continue a preexisting or
default power management mode.
From either of steps 314 or 316, the process next passes to step
318, which depicts the process becoming idle until another event or
activity entry is created in the user calendar. The calendar,
however, should be preconfigured to send a power management event
notification to the power manager when beginning date and time for
an event having a non-null calendar power management mode
associated with the event entry is reached.
Events may have a predetermined or configurable delay relative to
the start time of an event, so that the power management mode is
not entered immediately at the start of the corresponding event,
but at some predetermined time interval after the start of the
corresponding event. This allows users to set a delay if they may
need to keep working and decide to arrive late to the event (e.g.,
for a user arriving at a meeting five minutes after it starts). A
warning may be associated within the start of an event, reminding
the user of the event and allowing the user to select a delay for
the associated power management mode.
Also, when notifying the power management module of an event, the
calendar program should check events with are contiguous with or
overlap the subject event, notifying the power management module if
a selected power management mode should be continued beyond the
duration of the subject event, or changed at the end of the subject
event.
The process of employing calendar based power management, depicted
in FIG. 3B, begins at step 320, which illustrates the start date
and time of a scheduled event within a user's calendar being
reached. The process then passes to step 322, which depicts a
determination of whether a power management mode was specified for
the event and associated with the event entry. If so, the process
proceeds to step 324, which illustrates checking the system
activity. That is, keyboard and mouse activity may be checked, as
well as hard drive and network card activity.
The process then passes to optional step 326, which illustrates a
determination of whether the detected system activity conflicts
with the specified power management mode. For example, if the event
entry power management mode indicates that the user will be
unavailable and the system should be shut down for the duration of
the event, but system activity shows that the user is continuing to
use the system, the user may not wish to have the system shut down.
If such a conflict is detected, the process may proceed to optional
step 328, which depicts delaying or cancelling the power management
event notification.
If optional step 326 is not implemented, or if no conflict between
system activity and the specified power management mode is
perceived, the process proceeds instead to step 330, which
illustrates sending the power management event notification to the
power manager. The process may then proceed to optional step 332,
which again depicts a determination of whether detected system
activity conflicts with the specified power management mode.
Step 332 may be implemented in lieu of step 326, with the conflict
checking performed in the power manager after the power management
event notification has been received, or vice versa, with conflict
checking taking place within the calendar before the power
management event notification is sent. Alternatively, neither or
both of steps 326 and 332 may be implemented. In the latter case,
step 326 may be implemented only to check for system activity
indicating the presence of the user, while step 332 may be
implemented to further check for system activity indicating remote
access to the system, such as hard drive or network adapter
activity.
If step 332 is implemented and a conflict is perceived between the
power management event and the detected system activity, the
process may proceed to step 334, which illustrates delaying or
cancelling the power management event to be initiated in response
to the notification. If step 332 is not implemented, or if no
conflict exists between detected system activity and the power
management event to be initiated, the process proceeds instead to
step 336, which depicts entering the power management mode
specified by the power management event notification. The process
then passes to step 338, which illustrates the process becoming
idle until another scheduled event on the user's calendar is
reached.
The present invention allows entries within a user's calendar to be
associated with power management events, complementing and refining
the power management schemes employed within a data process system.
The invention is particularly beneficial in integrated systems
where hardware, operating system and applications are all
interlocked rather than disjointed or even contradictory. By making
applications such as Lotus Organizer or Lotus Notes Calendar assist
in controlling power management, rather than power management which
is blind to the user's schedule of activities as found in the prior
art, battery longevity may be improved.
The present invention may also be combined with program scheduling
utilities to improve overall performance. For example, if a
calendar entry causes the system to shut down for a user's
week-long vacation, the power manager may cause the system to power
up for execution of a scheduled program during that week (e.g., an
end-of-month online banking statement transfer), then shut down
following completion of the scheduled task.
It is important to note that while the present invention has been
described in the context of a fully functional data processing
system and/or network, those skilled in the art will appreciate
that the mechanism of the present invention is capable of being
distributed in the form of a computer usable medium of instructions
in a variety of forms, and that the present invention applies
equally regardless of the particular type of signal bearing medium
used to actually carry out the distribution. Examples of computer
usable mediums include: nonvolatile, hard-coded type mediums such
as read only memories (ROMs) or erasable, electrically programmable
read only memories (EEPROMs), recordable type mediums such as
floppy disks, hard disk drives and CD-ROMs, and transmission type
mediums such as digital and analog communication links.
While the invention has been particularly shown and described with
reference to a preferred embodiment, it will be understood by those
skilled in the art that various changes in form and detail may be
made therein without departing from the spirit and scope of the
invention.
* * * * *